US8920412B2ActiveUtilityPatentIndex 98
Electrosurgical generator for the treatment of a biological tissue, method for regulating an output voltage of an electrosurgical generator, and corresponding use of the electrosurgical generator
Est. expiryJun 30, 2028(~2 yrs left)· nominal 20-yr term from priority
A61B 2018/00827A61B 18/042A61B 18/1206A61B 2018/00892A61B 2018/00767
98
PatentIndex Score
229
Cited by
16
References
12
Claims
Abstract
An electrosurgical generator for the treatment of biological tissue. The electrosurgical generator comprises a generator part which supplies a high-frequency (“HF”) treatment current with an HF voltage set according to a voltage control signal. A measuring device detects the HF treatment current and the HF voltage and generates corresponding current and voltage signals. The current signal and the voltage signal are fed to a conversion device which forms a real current signal corresponding to the real component of the HF treatment current. A regulation device compares the real current signal with a pre-settable target value and generates the voltage control signal on the basis of the comparison. The real component of the treatment current is determined and the generator part is adjusted so that said real component approximates to a pre-determined target value.
Claims
exact text as granted — not AI-modifiedThe invention claimed is:
1. An electrosurgical generator for the coagulation of biological tissue by means of an inert gas plasma coagulation instrument, comprising
a generator part which supplies a high-frequency treatment current with a high-frequency voltage set according to a voltage control signal such that electrical energy is supplied to the biological tissue;
a measuring device for detecting the high-frequency treatment current and the high-frequency voltage for generating a corresponding current signal and a corresponding voltage signal;
a conversion device to which the current signal and the voltage signal are fed and which is configured such that a real current signal corresponding to the real component of the high-frequency treatment current is formed from the current signal and the voltage signal; and
a regulation device which compares the real current signal with a pre-settable target value and generates the voltage control signal on the basis of the comparison,
wherein the real component of the high-frequency treatment current is adjustable according to the target value for ensuring a tissue treatment that is independent of a distance between the tissue and an electrode of the inert gas plasma coagulation instrument when performing a contactless coagulation procedure.
2. The electrosurgical generator according to claim 1 , further comprising a power limiting device which determines a real power based on the current signal and the voltage signal and limits said real power to a pre-set value.
3. The electrosurgical generator according to claim 1 , further comprising a current limiting device which limits the real component of the treatment current to a pre-set value.
4. The electrosurgical generator according to claim 1 , further comprising a data input and data storage device for input and storage of real resistance components and reactive impedance components of attached surgical instruments and loads, wherein the data input and data storage device is connected to the conversion device, wherein the conversion device is configured to include the reactive impedance portions when calculating the real component of the high-frequency treatment current.
5. The electrosurgical generator according to claim 1 , wherein the conversion device comprises a computer device which forms the real current signal using one of:
a Hilbert transform,
a discrete Fourier transform,
a fast Fourier transform, and
a determination of mean power from N sample values and a determination of effective values of voltage and current, where mean power P is determined according to the equation
P
=
1
N
∑
k
=
1
N
u
(
k
)
·
i
(
k
)
where N is a positive integer, u(k) is the voltage signal at sample k, and i(k) is the current signal at sample k, and where effective values of voltage u eff and current i eff are determined according to the equations
u
eff
=
1
N
∑
k
=
1
N
(
u
(
k
)
)
2
i
eff
=
1
N
∑
k
=
1
N
(
i
(
k
)
)
2
wherein the real current signal i real,eff is given by
i real,eff =i eff ·cos φ
where
cos
φ
=
P
u
eff
·
i
eff
.
6. A method for regulating an output voltage of an electrosurgical generator which supplies a high-frequency treatment current at a high-frequency voltage for the coagulation of biological tissue by means of an inert gas plasma coagulation instrument, comprising the steps:
detecting the high-frequency treatment current and the high-frequency voltage and generating a corresponding current signal and a corresponding voltage signal;
forming a real component of the high-frequency treatment current from the current signal and the voltage signal and generating a corresponding real current signal;
comparing the real current signal with a pre-settable target value and generating a voltage control signal based on the comparison; and
regulating the output voltage such that the real component of the high-frequency treatment current corresponds to the target value,
wherein the real component of the high-frequency treatment current is adjustable according to the target value for ensuring reliable ignition of an inert gas plasma of the inert gas plasma coagulation instrument when performing a contactless coagulation procedure.
7. The method according to claim 6 ,
wherein the real current signal is formed using one of:
a Hilbert transform,
a discrete Fourier transform,
a fast Fourier transform, and
a determination of mean power from N sample values and a determination of effective values of voltage and current, where mean power P is determined according to the equation
P
=
1
N
∑
k
=
1
N
u
(
k
)
·
i
(
k
)
where N is a positive integer, u(k) is the voltage signal at sample k, and i(k) is the current signal at sample k, and where effective values of voltage u eff and current i eff are determined according to the equations
u
eff
=
1
N
∑
k
=
1
N
(
u
(
k
)
)
2
i
eff
=
1
N
∑
k
=
1
N
(
i
(
k
)
)
2
wherein the real current signal i real,eff is given by
i real,eff =i eff ·cos φ
where
cos
φ
=
P
u
eff
·
i
eff
8. A system for treatment of biological tissue, comprising:
an inert gas plasma coagulation instrument for the coagulation of biological tissue; and
an electrosurgical generator comprising:
a generator part which supplies a high-frequency treatment current with a high-frequency voltage set according to a voltage control signal such that electrical energy is supplied to the biological tissue;
a measuring device for detecting the high-frequency treatment current and the high-frequency voltage for generating a corresponding current signal and a corresponding voltage signal;
a conversion device to which the current signal and the voltage signal are fed and which is configured such that a real current signal corresponding to the real component of the high-frequency treatment current is formed from the current signal and the voltage signal; and
a regulation device which compares the real current signal with a pre-settable target value and generates the voltage control signal on the basis of the comparison,
wherein the real component of the high-frequency treatment current is adjustable according to the target value for ensuring a tissue treatment that is independent of a distance between the tissue and an electrode of the inert gas plasma coagulation instrument when performing a contactless coagulation procedure.
9. The system according to claim 8 , wherein the electrosurgical generator further comprises a power limiting device which determines a real power based on the current signal and the voltage signal and limits said real power to a pre-set value.
10. The system according to claim 8 , wherein the electrosurgical generator further comprises a current limiting device which limits the real component of the treatment current to a pre-set value.
11. The system according to claim 8 , wherein the electrosurgical generator further comprises a data input and data storage device for input and storage of real resistance components and reactive impedance components of attached surgical instruments and loads, wherein the data input and data storage device is connected to the conversion device, wherein the conversion device is configured to include the reactive impedance portions when calculating the real component of the high-frequency treatment current.
12. The system according to claim 8 , wherein the conversion device comprises a computer device which forms the real current signal using one of:
a Hilbert transform,
a discrete Fourier transform,
a fast Fourier transform, and
a determination of mean power from N sample values and a determination of effective values of voltage and current, where mean power P is determined according to the equation
P
=
1
N
∑
k
=
1
N
u
(
k
)
·
i
(
k
)
where N is a positive integer, u(k) is the voltage signal at sample k, and i(k) is the current signal at sample k, and where effective values of voltage u eff and current i eff are determined according to the equations
u
eff
=
1
N
∑
k
=
1
N
(
u
(
k
)
)
2
i
eff
=
1
N
∑
k
=
1
N
(
i
(
k
)
)
2
wherein the real current signal i real,eff is given by
i real,eff =i eff ·cos φ
where
cos
φ
=
P
u
eff
·
i
eff
.Cited by (0)
No later patents cite this yet.
References (0)
No backward citations on record.